Click Diagnostics has developed a PCR-based diagnostic test that is rapid (sample-to-answer <30 min), small, portable, disposable and that automatically performs and integrates sample processing, PCR amplification, and amplicon detection. Unlike other PCR platforms, the Click device does not require a separate instrument. The first clinical application of the Click platform will simultaneously detect 3 STIs, N. gonorrhoeae (NG), C. trachomatis (CT) and T. vaginalis (TV) in self-collected vaginal swabs, and has entered a pivotal 510k/CLIA waived, NIAID-funded clinical trial, with expected FDA approval in 2019. In this FastTrack project, we propose to add a critical new function to the existing multiplexed device ? determine whether an NG strain is ciprofloxacin sensitive. The CDC has identified drug resistant Neisseria gonorrhoeae as an urgent threat; nearly 30% of the ~820,000 new Neisseria gonorrhoeae (NG) infections each year are antibiotic resistant and have the potential to become virtually untreatable. Although only 19% of gonorrhea cases are ciprofloxacin resistant, the CDC recommends physicians prescribe ceftriaxone, a last resort antibiotic, for all cases of gonorrhea. Extensive scientific and clinical data suggest that ciprofloxacin resistant isolates harbor a single nucleotide polymorphism (SNP) at codon 91 of the gyrase A gene. Therefore, by identifying patients with the WT Ser91 in the gyrase A gene will provide individualized treatment to those susceptible to ciprofloxacin, thus minimizing the use of ceftriaxone. Click?s fast, accurate, patient-side test identifying antibiotic susceptibility would dramatically improve patient management, while extending the utility of last resort antibiotics. The goal of this project is to add, in Phase I, the capacity to detect WT gyrase A at Ser91 to the current Click STI assay and in Phase II, to integrate this assay onto the Click platform and carry out systematic preanalytical and preclinical testing to qualify the product for a clinical trial. Click has partnered with Jeff Klausner, MD (UCLA), a leading authority on diagnostics and treatment of STIs, and John SantaLucia, PhD (DNA Software), to assist in silico probe design, assay development, and testing. In Phase I, Click will optimize our probe detection method to ciprofloxacin sensitive WT Ser91 in the gyrA gene. Next, we will add the new NG cipro-susceptibility assay into the existing multiplexed assay and demonstrate that the new assay maintains the functionality of the current one with similar limits of detection, PCR efficiency, sensitivity, and specificity. In Phase II, Click will modify the device to integrate the multiplexed CT/NG/TV/NGciproS assay and enable volume manufacturing by reducing size, weight, and complexity of parts. Finally, we will perform preclinical and preanalytical studies on deidentified clinical isolates obtained from UCLA archive, which will provide preliminary sensitivity and specificity data and inform any assay and device adjustments required for analytical and clinical studies ahead of FDA approval. Successful completion of this work will yield a production version of a rapid, patient-side device capable of identifying CT/NG/TV and ciprofloxacin susceptible NG that is ready for clinical testing.